aboutsummaryrefslogtreecommitdiff
path: root/src/tsfn.cpp
diff options
context:
space:
mode:
authorKristian Evers <kristianevers@gmail.com>2018-12-26 10:53:01 +0100
committerGitHub <noreply@github.com>2018-12-26 10:53:01 +0100
commit81ec8c0b58d66333fccd3703dab62a11132a0331 (patch)
tree41b4675d169f849516649700ab4f50d4cffa4c02 /src/tsfn.cpp
parent355d681ed88019e97742344bd642c2fd97e700a1 (diff)
parent80dad6ef2bed4a83008db06986dc168918d48476 (diff)
downloadPROJ-81ec8c0b58d66333fccd3703dab62a11132a0331.tar.gz
PROJ-81ec8c0b58d66333fccd3703dab62a11132a0331.zip
Merge pull request #1203 from rouault/cpp_conversion
Conversion of most C files to C++
Diffstat (limited to 'src/tsfn.cpp')
-rw-r--r--src/tsfn.cpp16
1 files changed, 16 insertions, 0 deletions
diff --git a/src/tsfn.cpp b/src/tsfn.cpp
new file mode 100644
index 00000000..ea3b896d
--- /dev/null
+++ b/src/tsfn.cpp
@@ -0,0 +1,16 @@
+/* determine small t */
+#include <math.h>
+#include "projects.h"
+
+double pj_tsfn(double phi, double sinphi, double e) {
+ double denominator;
+ sinphi *= e;
+
+ /* avoid zero division, fail gracefully */
+ denominator = 1.0 + sinphi;
+ if (denominator == 0.0)
+ return HUGE_VAL;
+
+ return (tan (.5 * (M_HALFPI - phi)) /
+ pow((1. - sinphi) / (denominator), .5 * e));
+}